Video: Night eaters

It's a battle every night. As her neighbors sleep in a Philadelphia suburb, Christine Francy finds herself wide awake, sneaking around her own home, afraid to turn on a light— afraid someone might discover her obsession.

Christine Francy: This is my deep, dark secret.

It’s a secret she’s hidden from friends and family, but now, at the age of 55, she can no longer ignore it.

Christine: I feel bad, I feel guilty, and I'm like “I don't want to do it.”

What Christine is doing is eating, but not when most people do. She consumes almost half her calories — hundreds of them — in the middle of the night. For Christine, a midnight snack is more like a series of snacks that rob her of sleep, leaving her exhausted and depressed.

At what point do you realize that there is something wrong, this is not normal?

Christine: I saw this article at the gym a few months ago. I’m like, “Oh my God, that’s me.”

The article was about something called NES or Night Eating Syndrome, a disorder where people eat at least 25 percent of their daily calories late at night and overnight. Christine had never heard of NES, so she went on the Internet to find out more and that lead her to Dr. Kelly Allison, a research psychologist at the University of Pennsylvania, just an hour from Christine’s home.

Dr. Allison is conducting a research study on NES sufferers and asked Christine to join her group. Christine signed on and agreed to let Dateline – with our cameras rolling – record her eating and sleeping habits for several nights at her home.

And right away – even with us watching – she can’t control her urge to eat. On camera, you can see her tossing and turning and finally getting up. Down to the kitchen she goes to get a bowl of cereal and a glass of water – one of her favorite midnight snacks.

The clock records the time. It’s 3 a.m. She’ll eat again and again and again. She’s still munching at 7:45 in the morning and finally gets up at 9:05 a.m.

Dr. Kelly Allison: You were up at 10:30, 11:30, 12:15, 1:05, 2:05, 3:05. So, I mean that's not a…

Christine: Right.

Dr. Allison: …good night's sleep.

Christine: Right. No. Right.

And it’s more than a bad night’s sleep. Just listen to what Christine wrote in a diary Dr. Allison asked her to keep: “Disgusted with myself. Feeling like a freak.”

Christine is not alone. Dr. Allison says millions of people suffer from NES and she and her colleagues have written a book: Overcoming Night Eating Syndrome’ a step-by-step guide to breaking the cycle -- a vicious cycle of starving by day and grazing by night.

Dr. Allison: Not only are they carrying around all this guilt about their eating and shame and everything that goes with that, they're not functioning as well during the day. It affects your mood. You don't concentrate as well. Night eaters just don't feel rested.

Rob Stafford, Dateline correspondent: I guarantee you, a lot of people watching right now are saying, "This sounds like another psychobabble syndrome."

Dr. Allison: Right. Well, yeah. Why do we need another disorder, right? This is actually described way back in the '50s by my colleague Dr. Struckard. He realized at that point that it probably was a stress-related disorder, and I think more attention has been paid to it recently because of the obesity epidemic.

Dr. Allison says it’s a combination eating, stress, and sleeping disorder. Both women and men suffer from NES. In fact, men represent about 40 percent of the people diagnosed. A third of all patients battle obesity and the life-threatening health problems that go with it.

Christine is not obese, but she says she can’t get rid of the extra 10 pounds that she’s gained despite working out regularly with a trainer. And she says she feels a lot of stress as a divorced empty nester with two aging parents.

Christine: Loneliness-induced stress. I feel like there's a hole in my heart that's gotten translated into a hole in my stomach. That's what it feels like, the hole.

Stafford: So it's not about the food?

Christine: No, don't think so.

Dr. Allison's research study has discovered the treatment for NES is not a diet that deals with overeating, but an anti-depressant that deals with the stress and depression underlying the disorder. So far, it’s helped 70 percent of the study’s volunteers.

Christine: I thought, “Well, maybe some kind of medication would make it easier. It wouldn't be such a battle. Maybe I could sleep at night.”

And finally, success. Christine’s dirty little night secret is no more. She’s stopped her night snacking and now does all her eating at breakfast, lunch and dinner. She says the change is remarkable.

Christine: I would say the cravings have gone down by about 95 percent. It's not the monster that it used to feel like before. It's not the 24-hour hole in my stomach that I used to feel all day long.

Looking rested and thin, Christine says she not only lost 11 pounds, but also some of the anxiety that kept her up at night.

Christine: I guess the main thing is that I have my confidence back. I'm back to the person that I guess I used to be. To actually be aware of not being hungry, it's like a miracle to me to see food and not want it. It's just wonderful.

Dateline wires the home of a volunteer, Jenny, from top to bottom with hidden cameras. Then she called repairmen to her house for a simple problem we created as a test with Jenny's pool. NBC's Chris Hansen reports.